Method of reacting mercaptothiazoles with primary amines and formaldehyde



Patented Mar. 26, 1935 "UNITED METHOD: 50F REA'oriNe MEnoAPTo'rml "AZOLES -JWKTHPRHMARY AMINES AND FORMAL'DEHYDE- I 5 '22 Claims. (orgasm-44 This invention: relates 'to' a method of .preparing reactionproducts of mercaptothiazoles With primary aromatic amines and formaldehyde.

An object of this invention is'uto produce these 5 materials-from amercaptothiazolefia primary aromatic amine and formaldehyda without resorting to? the nsect-Volatile solvents as thereaction-'-medium, or expensive mixer'- processes wherein the heat or energyirequirements -are.

hig'hY -Other ob'ects willbe a p fr the description.- I

For the purpose of illustration, solelyi and irrespective of theory," it is assumed that these reaction products have -the general formula tuted aryl group andRris a. ,1thiazyl group,

and result. from reactinga mercaptothiazole with a methylene-primary, aromaticiamine (methylene base) which in "turn .is thereaction product of formaldehyde. and primary aromatic amine. Under certain conditions, as: .disclosedherein, the mercaptothiazole, theiformaldehydegand the primary. aromatic 'aminemayeach be brought together in aqueous solutionwherein the reaction proceeds to :produceproducts ".which :may have the above formula; :It isbelieved that both ,the original thiazyl groupand the mercaptan sulphur are preserved in the final compound. f; Broadly-the invention comprises mixing, an aqueous solution containing dissolved; therein a mercaptothiazoleand formaldehyde with a water soluble form of .a primary aromaticamine, vand more specifically":comprises.(1). making, an aqueous solution of a mercaptothiazole by dissolving it in wate'rin the form of a water-soluble fixed alkali or 'organicbasesalt incapable, of reacting With formaldehyde ..and .xmore strongly basic than i the -methylene base to be reacted, or dissolving it water containing aforesaid alkali or organic base,iv(2);;adding* to ;the aqueoeus solution formaldehyde, preferably in the form {Of an aqueous solution, with agitation;;and cooling-,-

thiazoleqform salts incapable} of; reactingiyvith l;

flll'OllS, yacetic, etc. maybe usedto' solubiliz .w' ias. h se ondary mater. and fixed alkali. or even organic base, are erebl us ne im ler u ti ie 1 The following e ramplepis-lgiyenlto I v theinvention and is not to be. "cons'trued"as' ing'thereof:

1 I ,5 Example 1 .83 g. f fl mercaptobenaothiaaole were dissolved .in 20 ggcepum "sodium; hydroxide and 1 000.' g. water. To-thissolutionjwere added approximately a1 g, of 37%,forn'1aldehy'de orthe 10 equivalent offormaldehydeK v 10,0 'Thisial aj line solution was agitated; and kept .c'oldgwhile asolutionof 46g; aniline and 5,3,gQconcent 'ated hydrochloric \acid in 600 g. water was lslo' wlyv added, The-charge as-cooled under agitat n 15 for a period of from 1 toahoursl' {The rystala n line product was=fi1 tered,oif, Washd, driedli any suitable ,manner so (that.v the; temperature did not reach the melting poifitof'tlie real product and then ground, .'I "h e. jhg;ht crystalline reactionp fOduct'wasthus" bta nearly quantitative yields, l eltin y t' Instead of, sodium -hydroxidfi, pota solubiliz e the mercaptothiazfcle} ingaoiueous .sQlur tion, including carbonates and bicarbonate-s Joli sodium: or-potassium, us n l-heat when necessar as well as organic bases;whichftogether with the formaldehydel and v rhicharegmore,strongly b than the methylene base to be reacted. his

steadof hydrochloric 'acid, -Whiph,is preie d: other; acids, .ior example nitric, sulphuric; sulr amine-end form soluble salts therewith.

eb nz ih az nis h wnbr h 9 s ing-.-structure -in which the. atom r,e.arium ered' C v v for the. purposes 10t the, invention asindicated:

andthen (3-) slowly mixing withthepool edsolu- I tion, an'aqueous solution of a primary. aromatic amine which has been acidified by addition of an acid. The acid and amine would'form the water soluble amine salt of i the acid;,in solutig -th e resulting-solution being, of ;a cidic,--'character. The primary amine-acid 150111131011 :may be added ito. the cooled alkaline solutiongof the mercapto -thiazole. and formaldehyde :orrvice versa ,-The

sprimary materials, e. ;g. the ;-:mercaptothiazole,

- formaldehyde randuprimary aromatic, amine, as

assemhave t'eiifgiveiis illustrati as rlinercantothiaaoles:

a ws? ,naphthylamine p-zx lidine,

'h drk n lins ah'i l d il 2 The products may be used as accelerators for the vulcanization of rubber and in this respect ,the following reaction products. are'particul'arly usefulz, The reaction product 'of formaldehyde,

5-.nitro.mercaptobenzothiazole and aniline; form aldehyde, 51-chlor. mercaptobenzothiazole and aniline formaldehyde, 'mercaptobenzothiazole and oor'p-toluidine; formaldehyde, mercapto benzothiazole and alpha or beta naphthylamine;

formaldehyde,- toluthiazole 5 and anilinej formaldehyde,mercaptobenzothiazole and aniline; formaldehyde; mercaptobenzothiazole and pxylithiazole, and. p-chlor aniline;. formaldehyde, 5-

zothiazole,formaldehyde and 2-5 dichloraniline.

It]i$.ft0 be understood that jin the claimsth, terms fbasic 'and-alkalinerefer only to a con uni arising from the use of fixed alkalis and aforementioned organic bases;

It will be apparent to those skilled in the art that certain modifications in' the amounts'of materials'specified in the preferred example may be made withoutkdepartingfrom the scope ofithe invention, as maybe required in the use of impure or commercial ,grades in place of chemically pure materials. For example, an excess'of fixed alkali may be used, sufficient to neutralize any in quantities. V

7 "salt of said mercaptoaryl thiazole, v

2;,A process offmakir'ig the reaction product ofiformaldehyde, a'2-mercapto-aryl-thiazole of formic .acid present in or arising from commercial-"grades off rmaIdehyde or: formed in situ during the reaction." Such modifications would be dependent on the comparative purity of the primary and secondary materials selected which, in turn, should preferably be present in equimothus -de scribed invention, what I jclaim'and desire tdproteCt by Letters Patent is:

1"." A process. ofimaking the reaction product of formaldehyde, a ,Z-mercapto-aryl-thiazole of the benzene'series, land a primary aromatic :amine ot. the benzene and naphthalene series, which comprises mixing an acid salt of said primaryaromatic amine withjakcooled' aqueous solution containing formaldehyde and an alkali-metal I the benzene se'ries, ;and' a primary aromatic aqueous solution ofan acidsalt of saidprimary aromatic amine, and recovering the precipitated crystalline reactioniproduct. :4. A processoflmaking the reaction produfi n of iformaldehyde, a}2-mercapto-arylthiazole of the ,benzeneseries',;5a primary aromatic famine 1 of the benzene, and naphthalene series, 'which eomprisesmixin'g at arelativelylowtemperature an aqueous solution offan acidsalt 'of saidprimaryq'aromatic amine with a cooled'aque- 'ous solution containing formaldehyde'andan -;alkali-metal salt 1 of said mercaptoa ryl 'thiazole.

"3; A process of making thereaction productgof formaldehyde; a 2 -mercapto-aryl-thiazoleofLthe benzene series, "and a primary aromatic amine of the benzene and, naphthalene series which comprises mixing formaldehyde with an aqueous alkaline solution ofisaid nercapt'oarylthiazole, cooling the solution and'mixin g therewith an .amine' of the benzene and naphthalene series,

, which comprises mixing formaldehyde with an aqueous alkaline solution of ,said mercaptoarylthiazole', cooling the solution and mixing thereof the benzene and napthalene series.

with an aqueous solution ofran acid salt 10f ani line, and recovering the precipitated crystalline reaction. product. 1

V 5. A process of making the reaction product, of formaldehyde, a 2-mercapto-aryl-thiazo1e of the benzene series, and faprimary aromatic amine of fth e benzene and naphthalene series,

which comprises preparing an aqueoussolution of formaldehyde and an a'lkali-metal'saltof 2- mercaptobenzothiazole;cooling the solution and mixing therewithari aqueous solution of hydro.- V chloric acid and aniline, and recovering the pre 11 cipitated' crystalline reaction product.

benzene series, 'andla primary aromatic amine .of the benzene" andi naphthalene series,-which comprises mixing formaldehydewith aqueous alkaline solution} or said mercaptoarylthiazole, i cooling the solution and mixing 1 therewith an aqueous solution of an acid saltof a toluidine,

6. A process of making the' reaction product of formaldehyde, a 2-mercaptoearyl-thiaz'ole of the.

and recovering the precipitated",crystallineiref action product. 7 4 "1,.A processoflmaking the reaction product a I of formaldehyde, 1a 2-mercapto-aryl-thiazole of the 'b'en'zenefseries, and a; primary aromatic amine of the benzene; and naphthalenei series, 7

which. comprises preparing an aqueousf solution vof formaldehyde. and an alkali-rmetalsalt-ofimercaptobenzothiaz'oleg cooling 1 the solution and mixing therewith aqueous solution. of hydrochloric. acid and-:orthoj toluidine',gand recovering the precipitated crystalline react-ion product.

8. A process of makingthe' reaction productof formaldehyde,- 9. 2-mercapto-aryl thiazole of the: benzene series,wand a primary aromatic amine; of the benzene and'naphthalenefseriespwhich comprises mixing formaldehyde with-an aqueous "aqueous solutionofan acid salt of a halogen substituted aniline, and recovering .theiprecipitated ,crystallinereactionproduct. s I reactiomproduct of 9."A'process of p formaldehyde, a Z-metcapto-aryl-thiazole or the alkaline solution of said, Qrnercaptoarylthiazole, V cooling the solution -andgmixing therewith an benzeneserie's; and a primary; aromatic amine}.

of the-benzene-and naphthalene-series, whichcomprises preparing an aqueous solution of formaldehyde'and an alkali-metal saltof 2-rnercap. 7

. '5 'therewith'an aqueous solution of hydrochloric 0 acid and orthochlor aniline, and recovering the tobenzothiazolefcooling the solution andmixing precipitated"crystalline reaction product.

10.A processrofgmaking' a'reaction ;product' having the probable general formula a RiS-CHgNHR' I 11] naphthalene series, and'Ri is a benzo-thiazyl group, which compfisesmixing'an aqueous solution containing formaldehyde and. a water. soluble salt of a 2-mercaptobenzothiazole with an wherein'R isaniaryl group of the benzene and aqueous solution of a primary aromatic amine saltof the benzene and naphthalene series.

11. A process of making a'reactionproduct' wherein R is an arylgroup of the benzene and naphthalene series, and R1 is a benzo-thiazyl- "group, which comprises mixing aqueous soluj-v v v tion containing formaldehyde and-aflxed alkali V V .65 havingjtheprobable generalformula V v h 7 salt ofa z-mercaptobenzothiazolewith an'aque ous solution of a primaryaromatic amine sal 12. A process of making areaction product having the probable general formula R1--S-CI -I z--NI-I,R, wherein R is an aryl group of the benzene and naphthalene series, and R1 is a benzo-thiazyl R1SCHeNI-IR;y

wherein R is an aryl group of. the ibenzene and naphthalene series, and R1 is a benzo-thiazyl group, which comprises mixing an-acid salt of a primary aromatic amine chosen from benzene and naphthalene series with a cooled aqueous solution containing formaldehyde and an alkali metal salt of a z-mercaptobenzothiazole. 7

14. A process of making areaction'product having the probable general formula wherein R is an aryl group of the benzene and naphthalene series, and R1 is a benzo-thiazyl group, which comprises mixing at a relatively low temperature an aqueous solution of an acid salt of a primary aromatic amine chosen from thebenzene and naphthalene series with a cooled aqueous solution containing formaldehyde and an alkali-metal salt of a 2-mercaptobenzothiazole.

15. A process of making a reaction product having the probable general formula* wherein R is an aryl group of the benzene and naphthalene series, and R1 is a benzo-thiazyl group, which comprises mixing formaldehyde with an aqueous .alkaline solution of a 2- mercaptoarylthiazole, cooling the solution and mixing therewith an aqueous solution of a mineral acid and a primary aromatic amine salt chosen from the benzene and naphthalene series, and

recovering the precipitated crystalline reaction product. I

16. A process of making a reaction product having the probable general formula 1 wherein R is an aryl group of, the benzene and naphthalene series, and R1 is a .benzo-thiazyl group, which comprises mixing formaldehyde with an aqueous alkaline solution of a 2'-mercaptobenzothiazole, cooling the solution and mixing therewith an aqueous solution of an acid salt of V 'Wherein R is an aryl group of the benzene and a primary aromatic amine chosen from the henzene and naphthalene series, and recovering the precipitatedcrystalline reaction product.

17. A process of makinga reaction product having the probable general formula- R1 s cH1-NH --R wherein R is an aryl group of the benzene and naphthalene series, and R1 is a benzo-thiazyl group, which comprises mixing formaldehyde with an aqueousalkaline solution of 2-mercapto benzothiazole, cooling the solution and mixing therewith'an aqueous solution of an acid salt of aniline, and recovering the precipitated crystal- 'line reaction product. v I 1 18. A process of making .a reaction product having the probable general formula R1-SCHzV-NHR.

wherein R is an aryl group of the benzene and naphthalene series, and R1 is a benzo-thiazyl gr0up,'which comprises preparing an aqueous so- V lution of formaldehyde and an alkali-metal salt of Z-mercaptobenzothiazole, cooling the solution and mixing therewith an aqueous solution of hydrochloric acid and aniline, and recovering the precipitated crystalline reaction product 19. A process of making a reaction'product having the probable general formula j R1S--CH2NHR wherein R is an aryl group of the benzene and naphthalene series, and R1 -is'a benzo-thiazyl group, which comprises mixing formaldehyde with an aqueous alkaline solution of a 2-mer- -captobenzothiazole, cooling the solution and mixwherein R is an aryl group of thebenzene and naphthalene series, and R1 is a benzo-thiazyl "group, which comprises preparing an aqueous solution of formaldehyde and an alkali-metal salt of 2-mercaptobenzothiazole, coolingthe so lution and mixing therewith'an aqueous solution I of hydrochloric acid'and'ortho' toluidine, and

recovering the precipitated crystalline reaction product.

21. A process of making a having the probable general formula reaction product wherein R is an aryl group of the benzene and naphthalene series, and R1 is a benzo-thiazyl group, which comprises mixing formaldehyde with an aqueous alkaline solution of .a 2-mercaptobenzothiazole, cooling the solution and mix- 1 1 ing therewith an aqueous solution of an acid salt 1 of a halogen substituted aniline, and recovering naphthalene series, and R1 is a benzo-thiazyl group, which comprises preparing an aqueous solution of formaldehyde and an alkalimetal lution and mixing therewith an aqueoussolution of hydrochloric acid and orthochlor aniline, and

-recovering the precipitated crystalline product.

WILLIAM EARL MESSER.

Q salt of Z-mercaptobenzothiazole, cooling the so;- 

